feat(store): draft states and discards are journaled, posted_seq is kept (P4)

Accounting reason: a draft that waits on its receipt, and one thrown
away, are facts about the books' working papers that must survive a
restart and replay identically, or a discarded draft would come back and
hold its period open. entry.draft_state_set and entry.draft_discarded are
drafts_v2's (an older version stops at the declaration instead of
misreading them); no figure moves. Schema 19 (taken at merge as the next
after the current last): entries.posted_seq, and a draft_states table
(drafts are not rows of entries, so the plan's entries.draft_state column
has nowhere to live). posted_seq is the journal line that posted each
entry (entry.posted, entry.reversed, the line that closed a period or
posted a schedule month), identical live and on replay.

8.0.6: a hand-written line of each new shape in
books_written_under_older_rules_still_open; fixture old-books/p4_before
written by 25b52580 (hand entries posted late, a reversal, a document, a
schedule month, a recurring draft, open drafts, a close) opens to the
same figures (serialized entries omit a building state, so no golden
moved); drafts_v2_is_its_own_feature; the fuzzer and GUI journal know the
types.

Tests: draft_states_replay_and_project, drafts_v2_waits_for_the_upgrade,
posted_seq_is_the_posting_lines_seq, an_older_version_stops_at_the_draft_events.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HS8WZziDnyxunC23MUxrLp

crates/ledger-gui/src/pages/journal.rs

@@ -426,6 +426,29 @@ pub fn describe(b: &Books, line: &JournalLine) -> Option<Event> {
             },
             Some(Route::Document(att)),
         ),
+        // A draft's state and a discard (plan P4): notes on a draft, no
+        // figure. A discarded draft is no longer an entry to open.
+        "entry.draft_state_set" => ev(
+            icon::PENCIL_SIMPLE,
+            match (
+                s(p, "state"),
+                p.get("note")
+                    .and_then(|v| v.as_str())
+                    .filter(|n| !n.is_empty()),
+            ) {
+                ("awaiting_evidence", Some(note)) => {
+                    format!("Draft #{id} waits for its evidence: {note}")
+                }
+                ("awaiting_evidence", None) => format!("Draft #{id} waits for its evidence"),
+                _ => format!("Draft #{id} is being built"),
+            },
+            Some(Route::Entry(id)),
+        ),
+        "entry.draft_discarded" => ev(
+            icon::TRASH,
+            format!("Draft #{id} discarded: {}", s(p, "reason")),
+            None,
+        ),
         "entry.settles" => {
             let settles: Vec<String> = p
                 .get("settles")